Norton Classic
The Classic is a motorcycle
A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...

 built in 1987 by Norton as a special edition of just 100 machines.

The Classic used an air-cooled twin-rotor Wankel engine
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...

 that had been developed by David Garside at BSA. Wankel engines run very hot, so Garside gave this air-cooled motor additional cooling air that was filtered and drawn first through the rotors and then through a large plenum into the combustion chambers via carburreters. The cool plenum (which doubled as a semi-monocoque
Monocoque is a construction technique that supports structural load by using an object's external skin, as opposed to using an internal frame or truss that is then covered with a non-load-bearing skin or coachwork...

 spine frame) and the transfer of latent heat
Latent heat
Latent heat is the heat released or absorbed by a chemical substance or a thermodynamic system during a process that occurs without a change in temperature. A typical example is a change of state of matter, meaning a phase transition such as the melting of ice or the boiling of water. The term was...

 during the carburation process significantly reduced the temperature of this fuel-air mixture, but its volumetric efficiency
Volumetric efficiency
Volumetric efficiency in internal combustion engine design refers to the efficiency with which the engine can move the charge into and out of the cylinders. More specifically, volumetric efficiency is a ratio of what quantity of fuel and air actually enters the cylinder during induction to the...

 was still somewhat impaired. The cooling air filter was mounted below the steering head (between the forks) to provide a partial ram air
Ram-air intake
A ram-air intake is any intake design which uses the dynamic air pressure created by vehicle motion to increase the static air pressure inside of the intake manifold on an engine, thus allowing a greater massflow through the engine and hence increasing engine power.The ram air intake works by...

 effect. The engine was lubricated by oil-injection, but the fuel-air mix also carried a mist of oil from the interior of the rotors, which helped to lubricate the rotor tips.

The fork stanchions were protected by rubber gaiters; and a full enclosure protected the final-drive chain. While its engine was revolutionary, in other respects, such as appearance, suspension and brakes,the Classic was a conventional standard motorcycle. The Classic was lighter and more powerful than its only Wankel competitor, the over-complicated single-rotor Suzuki RE-5 motorcycle.

The Classic was discontinued after a limited production run, and was succeeded by the liquid-cooled
Radiator (engine cooling)
Radiators are used for cooling internal combustion engines, mainly in automobiles but also in piston-engined aircraft, railway locomotives, motorcycles, stationary generating plant or any similar use of such an engine....

 Norton Commander
Norton Commander (motorcycle)
The Commander was a Norton motorcycle with a Wankel rotary engine.The first Norton Wankel motorcycle was the 1987 air-cooled Classic, built as a special edition of just 100 machines. It was followed by the air-cooled Interpol 2 model. The Commander was a liquid-cooled successor to the Interpol...

. Liquid cooling provided both greater reliability and greater power, at the expense of an arguably less attracive engine (which was concealed by a full fairing).

The Norton Wankel engine was further developed at Staverton
Gloucestershire Airport
Gloucestershire Airport , formerly Staverton Airport, is located at Staverton, in the Borough of Tewkesbury within Gloucestershire, England. It lies west of Cheltenham, near the city of Gloucester and close to the M5 motorway. According to the sign at the airport's entrance it is Gloucestershire's...

 into the MidWest aero-engine. The Midwest engine increased output from 85 bhp to nearly 110 bhp by improving volumetric efficiency, achieved by dumping overboard (rather than burning) the hot rotor cooling air, and by feeding fresh cool air to the combustion chambers.
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